<?php 
use think\Db;
use think\Config;
use think\Session;
use think\Request;
use think\Loader; 
 class Aes
 {
     protected $cipher = MCRYPT_RIJNDAEL_128;
     protected $mode = MCRYPT_MODE_ECB;
     protected $pad_method = NULL;
     protected $secret_key = '123456';
     protected $iv = '';

     public function set_cipher($cipher)
     {
         $this->cipher = $cipher;
     }

     public function set_mode($mode)
     {
         $this->mode = $mode;
     }

     public function set_iv($iv)
     {
         $this->iv = $iv;
     }

     public function set_key($key)
     {
         $this->secret_key = $key;
     }

     public function require_pkcs5()
     {
         $this->pad_method = 'pkcs5';
     }

     protected function pad_or_unpad($str, $ext)
     {
         //echo $ext;
         if ( is_null($this->pad_method) )
         {

             return $str;
         }
         else
         {
             $func_name = __CLASS__ . '::' . $this->pad_method . '_' . $ext . 'pad';
             //echo $func_name;
             if ( is_callable($func_name) )
             {
                 $size = mcrypt_get_block_size($this->cipher, $this->mode);
                 $a =  call_user_func($func_name, $str, $size);
                 return $a;


             }
         }
         return $str;
     }

     protected function pad($str)
     {
         return $this->pad_or_unpad($str, '');
     }

     protected function unpad($str)
     {
         return $this->pad_or_unpad($str, 'un');
     }

     public function encrypt($str)
     {
         $str = $this->pad($str);
         $td = mcrypt_module_open($this->cipher, '', $this->mode, '');

         if ( empty($this->iv) )
         {
             $iv = @mcrypt_create_iv(mcrypt_enc_get_iv_size($td), MCRYPT_RAND);
         }
         else
         {
             $iv = $this->iv;
         }
         mcrypt_generic_init($td, hex2bin($this->secret_key), $iv);
         $cyper_text = mcrypt_generic($td, $str);
         $rt = bin2hex($cyper_text);
         mcrypt_generic_deinit($td);
         mcrypt_module_close($td);

         return $rt;
     }

     public function decrypt($str){
         $td = mcrypt_module_open($this->cipher, '', $this->mode, '');

         if ( empty($this->iv) )
         {
             $iv = @mcrypt_create_iv(mcrypt_enc_get_iv_size($td), MCRYPT_RAND);
         }
         else
         {
             $iv = $this->iv;
         }
         mcrypt_generic_init($td, self::hex2bin($this->secret_key), $iv);
         $decrypted_text = mdecrypt_generic($td, self::hex2bin($str));
//        $decrypted_text = mdecrypt_generic($td, base64_decode($str));
         $rt = $decrypted_text;
         mcrypt_generic_deinit($td);
         mcrypt_module_close($td);
         return $this->unpad($rt);
     }

     public static function hex2bin($hexdata) {
         $bindata = '';
         $length = strlen($hexdata);
         for ($i=0; $i< $length; $i += 2)
         {
             $bindata .= chr(hexdec(substr($hexdata, $i, 2)));
         }
         return $bindata;
     }

     public static function pkcs5_pad($text, $blocksize)
     {
         $pad = $blocksize - (strlen($text) % $blocksize);
         return $text . str_repeat(chr($pad), $pad);
     }

     public static function pkcs5_unpad($text)
     {
         $pad = ord($text{strlen($text) - 1});
         if ($pad > strlen($text)) return false;
         if (strspn($text, chr($pad), strlen($text) - $pad) != $pad) return false;
         return substr($text, 0, -1 * $pad);
     }
 }